217999073 has 2 divisors, whose sum is σ = 217999074. Its totient is φ = 217999072.

The previous prime is 217999051. The next prime is 217999087. The reversal of 217999073 is 370999712.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 206554384 + 11444689 = 14372^2 + 3383^2 .

It is a cyclic number.

It is not a de Polignac number, because 217999073 - 2⁸ = 217998817 is a prime.

It is not a weakly prime, because it can be changed into another prime (217999013) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 108999536 + 108999537.

It is an arithmetic number, because the mean of its divisors is an integer number (108999537).

Almost surely, 2^217999073 is an apocalyptic number.

It is an amenable number.

217999073 is a deficient number, since it is larger than the sum of its proper divisors (1).

217999073 is an equidigital number, since it uses as much as digits as its factorization.

217999073 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 214326, while the sum is 47.

The square root of 217999073 is about 14764.7916680189. The cubic root of 217999073 is about 601.8453124039.

The spelling of 217999073 in words is "two hundred seventeen million, nine hundred ninety-nine thousand, seventy-three".